tel systems that PERC would never be installed under, the alternative is to disable pass-through in all cases which could be reported as another regression. Pass-through is used for SCSI Generic access to the physical devices, or for the management applications to properly function. In systems where this patch has disabled pass-through because it is unsupportable in combination with I/O performance, the user can choose to enable pass-through by turning off dacmode (aacraid.dacmode=3D0) or limiting the discovered kernel memory (mem=3D4G) with an associated loss in runtime performance. If we chose instead to turn off 64 bit dacmode for the adapters with this quirk, then this would be reported as another regression. Signed-off-by: Mark Salyzyn Signed-off-by: Andrew Morton Signed-off-by: James Bottomley BoŻnš9x